Conveyor systems are commonly used to convey articles to and through a processing station wherein various processing operations may be performed, such as a working operation on the article, an inspection operation on the article, or the like. Frequently, it is necessary or desirable that the article be firmly retained in place at the time the processing operation is formed. This may require moving the article from the conveyor system to a table equipped with a retainer arrangement, such as mechanical clamping elements, a vacuum system, or the like, for firmly retaining the article on the table during the performance of the processing operation, and then returning the article to the conveyor system after the processing operation has been completed.